The rubidium isotope 87/37Rb, a emitter with a half-life of 4.75 X 1010 yr, is used to

Question:

The rubidium isotope 87/37Rb, a β emitter with a half-life of 4.75 X 1010 yr, is used to determine the age of rocks and fossils. Rocks containing fossils of ancient animals contain a ratio of 87/38Sr to 87/37Rb of 0.0160. Assuming that there was no 87/38Sr present when the rocks